My kid faces a whole group of bullies today, can you give him some encouragement before school?

My kid had a mental health crisis and made his year last year hell. Today is the first day back at school and he's going to have to face them.

One girl lead him on then made fun of him and told everyone. It's gonna be a tough day.

Can you Redditors give him (15) some words of encouragement? Thank you!